fix codacy suggestions

[rachx]

fixes #105

[coveralls]

Coverage remained the same at 84.693% when pulling 8001221 on fix-codacy-suggestions into 2312264 on master.

[coveralls]

Coverage remained the same at 84.693% when pulling a88d2ea on fix-codacy-suggestions into 2a87483 on master.

[burnflare]

I guess I broke something by being too aggressive, looking at it now

[burnflare]

@INCENDE Any idea why my changes in this PR has caused LogicManagerTests to fail? Take a look at the travis log then search for "failed"

seedu.agendum.logic.LogicManagerTest > execute_load_successful FAILED
    java.lang.AssertionError: expected:<seedu.agendum.commons.core.UnmodifiableObservableList@72232657> but was:<seedu.agendum.commons.core.UnmodifiableObservableList@1>
        at org.junit.Assert.fail(Assert.java:88)
        at org.junit.Assert.failNotEquals(Assert.java:834)
        at org.junit.Assert.assertEquals(Assert.java:118)
        at org.junit.Assert.assertEquals(Assert.java:144)
        at seedu.agendum.logic.LogicManagerTest.assertCommandBehavior(LogicManagerTest.java:120)
        at seedu.agendum.logic.LogicManagerTest.execute_load_successful(LogicManagerTest.java:933)

[burnflare]

@INCENDE